Knock-on sweep structure and tools therefor

ABSTRACT

Sweep retaining structure includes a spring wire retainer with a base supported in a groove on the underside of the wedge support which mates with a stem portion of the sweep. The wedge support is apertured, and a central curved portion of the retainer passes through the aperture and supports a sweep-contacting end above the surface of the wedge support. The end is biased toward a contact area on the sweep to engage the area and eliminate sweep loss problems by preventing the sweep from slipping downwardly from the mounted position. To remove the sweep, a tool is inserted through the slot to depress the retainer end, and the sweep is forced off the wedge support. A raised area on the sweep directs soil away from the retainer and contact area to reduce wear and eliminate depression of the end during operation. The underside of the raised area positions the wire end and provides bend-resisting support for the wire.

FIELD OF THE INVENTION

[0001] The present invention relates generally to tillage tools and,more specifically, to a knock-on sweep and structure for preventing thesweep from falling off the end of a shank.

BACKGROUND OF THE INVENTION

[0002] Standard assemblies for implements such as chisel plows and fieldcultivators typically include a spring trip shank assembly extendingdownwardly to a tool-receiving end which mounts a shovel, point orsweep. Previously available mounting structure included bolts extendingthrough holes in the tool and the shank to secure the tool. When thetool in such an assembly has to be replaced because of wear or damage,the bolts must be removed. Wear and corrosion of the bolts substantiallyhinders removal and often makes the replacement a difficult andtime-consuming task.

[0003] Several solutions to the problem of easily and quickly replacingworn elements such as sweeps on shanks have been developed over theyears, including adapter brackets providing a self-locking fit with amatching taper on knock-on sweeps. Frangible pins and bolts have alsobeen suggested. However, most retaining devices have suffered from oneor more problems, including need for additional parts and the loss ofsweeps when encountering high removal forces during transport and duringrebounding of the shank from a tripped position. To reduce incidences ofsweeps falling off the shanks in quick mount arrangements, somemanufacturers have offered detent mechanisms such as a retaining clip inthe form of a sheet metal stamping with a spherical protrusion that fitsinto a hole in the sweep. To release the sweep, a screwdriver or othertool is used to depress the clip and move the protrusion away from thehole. Other detent arrangements are shown, for example, in U.S. Pat.Nos. 3,061,021 and 6,289,996. Such detents generally help retain thesweeps on the shanks, but the forces exerted on a sweep, particularlyforces exerted on deep tillage tools, can be so great that the sweepfails to stay on the shank. The geometry of most previously availablesweep detent arrangements, including non-symmetrical mating surfaces onsome, usually limits penetration of the retaining surface into the holeso that retaining forces are limited. Some care must be taken to alignthe protrusion with the hole, and part tolerances, variations in forceused to mount the sweep, or lack of indexing of the clip relative to theshank can make such alignment troublesome. A relatively small, rampedcontact area between the clip and the hole also increases the potentialfor losing a sweep. Soil moving up and around the stem portion of thesweep can move the clip from the detent position or wear away the clipuntil it is ineffective for holding the sweep on the shank. Extremeforces on the detent, such as those which occur during rebound, can alsocause deformation of the detent. If the detent deforms, loosened sweepscan unacceptably dangle from the shank or be lost. A hefty detentconstruction or frequent detent replacements are therefore usuallyrequired.

BRIEF SUMMARY OF THE INVENTION

[0004] It is therefore an object of the present invention to provide animproved sweep retaining structure for a knock-on sweep that overcomesmost or all of the above-mentioned problems. It is another object toprovide such an improved sweep retaining structure which is simple andinexpensive to manufacture and assemble and yet reliably holds the sweepon the shank and facilitates quick and easy removal of the sweep.Further objects include providing an improved sweep and providing animproved retainer for use with such structure.

[0005] It is yet another object to provide an improved sweep retainingstructure which provides reliable retention independently ofmanufacturing tolerances, forces applied during sweep mounting andprecise alignment of mating portions of the sweep assembly. It isanother object to provide such a structure having an improved andsimplified retainer mounting arrangement. It is a further object toprovide such a structure wherein the retainer is positioned for properengagement with a contact area on the sweep without direct contact witha bolt or similar fastener. It is still another object to provide such astructure having support and guidance structure for the detent tofacilitate alignment and prevent bending of the detent.

[0006] It is yet another object to provide an improved sweep retainingstructure which eliminates need for flat retaining clips and whichprovides improved wear and retaining characteristics compared to atleast most previously available clip type retaining structures. It isanother object to provide such a sweep retaining structure with integralretainer guide and wear reducing structure for improving retention andpreventing retainer deformation.

[0007] Sweep retaining structure constructed in accordance with theteachings of the present invention includes a retainer fabricated fromwire spring material and including a bent wire base supported in agroove on the underside of the wedge support which mates with stemportion of the sweep. The wedge support is apertured, and a centralcurved portion of the retainer passes through the aperture and supportsa sweep-contacting end above the surface of the wedge support. The endis biased toward a contact area on the sweep, preferably the top edge ofa slot in the stem, to engage the area and eliminate sweep loss problemsby preventing the sweep from slipping down away from the wedged mountedposition. To remove the sweep, a tool is inserted through the slot todepress the retainer end, and the sweep is forced downwardly off thewedge support.

[0008] The retainer is simple, inexpensive and reliable. The groovesupport eliminates a separate retainer fastening bolt or contact with afastening bolt and improves ease of assembly, proper positioning andwearability of the retainer. The retainer can be easily slipped intoposition on the wedge support.

[0009] The slot in the stem is preferably located near the top of theconnecting portion and defines an end contact edge. To protect the edgeand the end of the retainer from wear as well as prevent soil and debrisfrom depressing the end, a portion of the stem directly ahead of theslot is raised relative to the remainder of the surface of the stem andrelative to the contact edge. The raised portion directs the soil anddebris away from the slot. The underside of the raised portion defines aretainer guiding and support channel which holds the wire end in theoptimum sweep locking position and provides support for the wire toeliminate retainer deformation when high sweep removal forces areencountered during operation. The operator can clearly see if the sweepis properly wedged onto the sweep support by simply viewing the positionof the wire end relative to the contact edge and the guiding and supportchannel.

[0010] In one embodiment of the sweep, a central portion just below thestem also includes a raised area to help direct material away from thestem to improve stem life and assist in reducing wear in the slot areaand in the end of the retainer.

[0011] These and other objects, features and advantages of the presentinvention will become apparent to one skilled in the art upon readingthe following detailed description in view of the drawings.

BRIEF DESCRIPTION OF THE INVENTION

[0012]FIG. 1 is a side perspective view of a lower portion of a shankassembly including a sweep and sweep retaining structure constructed inaccordance with the teachings of the present invention.

[0013]FIG. 2 is an enlarged bottom perspective view of a portion of theassembly of FIG. 1, partially cut away to better show the sweepretaining structure and including a portion of a sweep removing tool.

[0014]FIG. 3 is a top view of the retainer for the structure of FIGS. 1and 2.

[0015]FIG. 4 is a side view of the retainer of FIG. 3.

[0016]FIG. 5 is a perspective view of the retainer of FIG. 3.

[0017]FIG. 6 is an enlarged perspective view of the sweep removing toolof FIG. 2.

[0018]FIG. 7 is a view similar to FIG. 1 and including a modifiedversion of a tool having sweep attaching, sweep removing and dirtremoving structure, the tool shown in a position for mounting the sweep.

DETAILED DESCRIPTION OF THE INVENTION

[0019] Referring now to FIG. 1, therein is shown the lower portion of aspring trip shank assembly 10 including a shank 12 having a lowertool-mounting end 14 supporting a knock-on sweep assembly 18. Theassembly 18 includes a wedge-shaped adapter bracket or sweep support 20having an aft face conforming to the forward face of the end 14. Thesupport 20 is secured to the end by two plow bolts (not shown) extendingthrough apertures 22 (FIG. 2) in the sweep support 20 and correspondingapertures in the end 14 of the shank 12. An earthworking tool 30, shownas a sweep in FIGS. 1 and 2, includes a forwardmost tip or point 32 andopposed wing portions 34 diverging outwardly in the rearward direction.An downwardly and rearwardly concave sweep mounting portion or stem 36includes edges 38 which wrap partially around the bracket 20. Theportion 36 provides a wedge fit between the tool 30 and the lower end 14of the shank 12 when the tool 30 is knocked on the sweep support 20. Theportion 36 is slid upwardly over the bracket 20 and then the tool 30 isdriven upwardly and rearwardly by several sharp blows from a hammer towedge the tool into the mounted position on the shank 12.

[0020] The sweep mounting portion 36 and the sweep support 20 firmlysupport the tool 30 on the end 14 without need for mounting boltsdirectly connected to the sweep 30. Since sweep mounting bolts areeliminated, the sweeps can be quickly driven from the support 20 andeasily replaced. However, rebound forces and the like can loosen thewedge fit while operating in the field. To prevent loss of the tool 30if the wedge fit is loosened during operation, retaining structureindicated generally at 40 is provided. The normal forces operating on asweep working in the ground tend to urge the sweep back into the wedgefit or mounted position if the sweep can be retained on the sweepsupport 20 after the undesired loosening.

[0021] The sweep retaining structure 40 includes a contact area 50centrally located at the upper portion of the stem or attaching portion36. A bent wire retainer 54 made of spring steel having a generallyround cross section is carried by the sweep support 20 and includes acontact end 58 which is offset forwardly and above the top or forwardsurface of the sweep support 20. The contact end 58 is biased into alocking position (FIGS. 1 and 2) wherein the flat end 58 abuts themating flat contact area 50 when the sweep 30 is in the mounted positionas shown. The surfaces of the area 50 and the end 58 are preferablyparallel to each other when in contact. The contact prevents the sweepfrom moving away from the mounted position until the end 58 is movedtoward the sweep support 20 against the bias.

[0022] The sweep support 20 includes an aperture 60 (FIG. 2) locatedbetween the plow bolt receiving apertures 22, and the bent wire retainer54 includes a central portion 54 c which projects through the aperture60. The bent wire retainer 54 includes a bent wire base portion 54 bwhich lies generally in a plane. The sweep support 20 has a front side20 f facing the sweep stem 36 and an opposite rear side 20 r, and thebent wire base portion 54 b is supported in an arc-shaped groove 66partially surrounding the top plow bolt aperture 22 on the rear side 20r. The base 54 b of the bent wire retainer 54 is captured between theforward face of the shank end 14 and the groove 66 when the support 20is attached to the shank 12. Good wire retainer support and positioningis thus provided independently of any separate fasteners or need forcontact with a plow bolt. During assembly, the end 58 of the bent wireretainer 54 is simply inserted through the aperture 60, and the baseportion 54 b is positioned in the groove 66.

[0023] The stem 36 of the sweep 30 includes a raised soil deflectionarea 70 which also defines a retainer guiding and support area on theunderside of the raised area. The underside of the raised area 70 isconcave downwardly and rearwardly and opens in the rearward directiontowards the contact area 50 (see FIGS. 2 and 4). The underside of thearea 70 receives a portion of the bent wire retainer at a location 54 goffset from the end 58 and guides the end 58 towards the contact area 50as the sweep 30 is driven towards the wedged mounted position. The wireretainer 54 is bent adjacent the location 54 g (see FIGS. 4 and 5) sothe axis 58 a of the end 58 is substantially perpendicular to the planeof the contact area 50. The contact area 50 is preferably the aft edgeof a slot 72 located rearwardly adjacent the raised area 70. The top ofthe edge lies along surface 36 t of the stem 36 and is protected by theraised area 70 which extends a substantial distance above the surface todeflect dirt and debris away from the edge and the retainer 54.

[0024] The rearward face of the end 58 is parallel to the plane of thecontact area 50 when the sweep is mounted and the end 58 of the bentwire retainer 54 is in the locking position. As the sweep is drivenupwardly and rearwardly onto the sweep support 20, the end 58 is urgeddownwardly until the contact area 50 passes the end 58 of the retainer.The location 54 g then springs into the channel-shaped underside of thearea 70 so the end 58 is held in the proper position relative to thecontact area (FIG. 4). If the sweep 30 begins to move downwardly awayfrom the wedged position, the contact between the end 58 and the contactarea 50 holds the sweep closely adjacent the fully wedged position untilthe soil forces acting on the sweep during operation again wedge thesweep into the locked position. The channel-shaped underside at 70 alsosupports the end 58 of the wire retainer 54 at points generally on-axisto help the retainer resist bending moments that would otherwise occurwhen strong sweep-removing forces such as rebound forces are acting todislodge the sweep. Without the support of the channel-shaped underside,the retainer could easily be deformed by the forces.

[0025] Referring to FIGS. 2 and 6, a removal tool 80 is shown whichincludes a handle 82 supporting a removal end 84 with a support 86adapted for positioning against the assembly 10 and a retainerdepressing extension 88 positioned above the slot 72 and the end 58. Thehandle 82 is moved towards the sweep 30 to depress the end of the wireretainer 54 below the contact area 50. A hammer is then used to impact aflat surface 90 above the removal end 84 to drive the sweep from theassembly. Transversely spaced ears 92 engage the top edge of the stem 36for positive tool positioning and sweep engagement and good distributionof impact forces.

[0026] In an alternate embodiment 80′ shown in FIG. 7, an attaching tool100 is supported from the handle 82′ and includes a V-shaped member 102generally conforming to the forward soil engaging portion of the sweep30 and adapted for being slidably received over the sweep as shown. Aflattened impact area 110 is offset from the sweep point on the side ofthe handle opposite the member 102. After slipping the sweep 30 onto thesweep support 20, the operator can wedge the sweep in the securedposition by hitting the area 110 with several sharp blows of a hammer.The member 102 covers the leading point and edge area, distributes thedriving force and protects the sweep from damage. A screwdriverattachment or soil engaging end 112 is attached to the end of the handle82′ opposite the removal end 84.

[0027] An additional raised area 120 is formed in the surface of thesweep 30 rearwardly of the point 32 just below the area where the stem36 connects to the remainder of the sweep. The raised area directs soiland debris outwardly from the stem 36 to increase stem wear life. Inaddition, the area 120 aids the raised area 70 in directing soil awayfrom the retainer 54 and the contact area 50 for more reliable sweepretention and increased sweep retainer structure life.

[0028] Having described the preferred embodiment, it will becomeapparent that various modifications can be made without departing fromthe scope of the invention as defined in the accompanying claims.

We claim:
 1. A knock-on sweep assembly for a tillage implement sweephaving a forward cutting edge, the assembly including a sweep support, asweep mounting portion located rearwardly of the cutting edge and matingwith the sweep support, the sweep mounting portion providing afastenerless tight but releasable fit when the sweep is in a mountedposition on the sweep support, and retaining structure for preventingthe sweep from dislodging from the sweep support, the retainingstructure including a contact area on the mounting portion, and a bentwire retainer supported by the sweep support and having an end, the endoffset from the sweep support and biased into a locking position whereinthe end abuts the contact area when the sweep is in the mounted positionand prevents the sweep from moving away from the mounted position untilthe end is moved toward the sweep support against the bias.
 2. The sweepassembly as set forth in claim 1 wherein the sweep support is apertured,and the bent wire retainer projects through the aperture.
 3. The sweepassembly as set forth in claim 2 wherein the bent wire retainer includesa bent wire base portion, the sweep support has a front side facing thesweep and an opposite rear side, and the bent wire base portion issupported on the rear side.
 4. The sweep assembly as set forth in claim1 wherein the sweep includes a retainer guiding and support areareceiving a portion of the bent wire retainer at a location offset fromthe end and guiding the end towards the contact area during mounting ofthe sweep and supporting the end in alignment with the contact area. 5.The sweep assembly as set forth in claim 1 wherein the contact areacomprises a slot in the sweep mounting portion having a rearward edgecontacting the end when the sweep is in the mounted position and the endis in the locking position.
 6. The sweep assembly as set forth in claim4 wherein the sweep mounting portion includes a surface and the upperedge extends downwardly from the surface, and wherein the retainerguiding and support area comprises a raised portion projecting above thesurface to prevent soil from wearing the contact area and preventing theend from being moved against the bias toward the sweep support by thesoil.
 7. Retaining structure for a knock-on sweep assembly for a tillageimplement sweep having a forward cutting edge and a sweep mountingportion located rearwardly of the cutting edge, the retaining structureincluding: a wedge support adapted for mating with the sweep mountingportion and providing a tight but releasable fastenerless wedged fitposition; and a bent wire retainer supported by the wedge support andhaving a locking end, the locking end offset from the wedge support andbiased into a locking position wherein the end abuts the sweep mountingportion and prevents movement of the sweep from the wedged fit position.8. The retaining structure as set forth in claim 7 wherein the wedgesupport includes an arced groove and the bent wire retainer includes anarced portion conforming to the shape of the arced groove and supportingthe retainer therein with the locking end offset from the groove.
 9. Theretaining structure as set forth in claim 6 wherein the wedge supportincludes a sweep side, a rear side opposite the sweep side, and anaperture extending between the sweep and rear sides, wherein the bentwire retainer includes a mounting portion supported on the rear side,and a central portion projecting through the wedge support aperture andsupporting the locking end above the sweep-facing side.
 10. Theretaining structure as set forth in claim 9 wherein the retainer portionis curved and lies generally in a first plane and the central portionincludes a reverse bend supporting the locking end above the firstplane.
 11. The retaining structure as set forth in claim 9 wherein themounting portion is supported from the rear side independently ofcontact with a fastener.
 12. The retaining structure as set forth inclaim 10 wherein the wedge support includes a mounting hole forreceiving a mounting bolt fastener to secure the retaining structure toa shank member, and the retainer portion includes a groove partiallyencircling the mounting hole.
 13. The retaining structure as set forthin claim 12 wherein the mounting portion is adapted for capturing in thegroove by the shank out of contact with the mounting bolt fastener. 14.A knock-on sweep for a tillage implement including a wedge mount toolsupport for securing the sweep in a wedged position on a shank forforward movement through soil, and a retaining structure biased intoengagement with the sweep when the sweep is in the wedged position toprevent the sweep from dislodging from the sweep support, the retainingstructure movable against the bias out of engagement with the contactportion for removing the sweep from the shank, the knock-on sweepcomprising: a mounting portion adapted for wedging on the tool support;a central point located forwardly and below the mounting portion;forward edges extending outwardly and rearwardly from the central point;a top surface portion extending upwardly and rearwardly from the pointto the mounting portion and defining a generally downwardly andrearwardly curved surface; a contact surface extending below the surfaceand adapted for contacting the retaining structure when the retainingstructure is biased into engagement with the sweep; and the mountingportion including a central raised area forwardly adjacent the contactsurface and offset above the surface to thereby deflect soil away froman uppermost boundary of the contact surface to prevent wearing away ofthe contact surface and prevent contact of the retaining structure withthe soil.
 15. The sweep as set forth in claim 14 including a lower soildeflecting surface located behind the point and below the central raisedarea, the deflecting surface offset above the surface adjacent themounting portion to deflect soil away from the mounting portion and theretaining structure.
 16. The sweep as set forth in claim 14 including aguide portion for receiving and positioning the retaining structure forengagement with the contact structure.
 17. The sweep as set forth inclaim 16 wherein the guide portion comprises an underside surface of thecentral raised area.
 18. The sweep as set forth in claim 17 wherein theunderside surface opens towards the contact surface.
 19. Retainingstructure for a knock-on sweep for a tillage implement including awedge-mount sweep support carried by a shank for securing a stem portionof a sweep in a wedged position on the shank for forward movementthrough soil, the retaining structure comprising: a wire retainer havinga base portion bent to conform to and be supported by a portion of thesweep support, a central portion extending upwardly from the baseportion, and a shank-contacting end opposite the base portion adaptedfor abutting sweep, the central portion biasing the shank contacting endinto a shank-contacting locking position.
 20. The retaining structure asset forth in claim 19 wherein the shank-contacting end is biased intoengagement with the sweep when the sweep is in the wedged position toprevent the sweep from dislodging from the sweep support, theshank-contacting end movable against the bias out of engagement with thecontact portion for removing the sweep from the shank.
 21. The retainingstructure as set forth in claim 19 wherein the base portion is bentgenerally into the form of an arc lying in a plane, the central portionis U-shaped and opens generally in a direction towards the arc andsupports the shank contacting end over the arc.
 22. The retainingstructure as set forth in claim 19 wherein the base portion is adaptedfor receipt around but out of contact with a fastener for the sweepsupport.
 23. The retaining structure as set forth in claim 19 whereinthe retainer includes a guided portion located between the centralportion and the shank-contacting end and adapted for contact with aportion of the sweep for guiding the end into the locking position. 24.An assembly and disassembly tool for a knock-on sweep assembly of atillage implement including a wedge mount for securing a sweep in awedged position on a sweep support independently of sweep mountingbolts, the sweep having an attaching portion and a forward soil engagingportion, and a retainer engaging the attaching portion and having alocking position to prevent the sweep from dislodging from the sweepsupport, the retainer movable from the locking position to a releaseposition for removing the sweep, the assembly and disassembly toolcomprising: a handle, a removal end connected to the handle andincluding retainer engaging member for movement of the retainer from thelocking position to the release position, the removal end also includinga first impact receiving surface for impacting the removal end when theretainer is in the release position and driving the sweep from the wedgemount; and an attaching end supported from the handle and including asweep engaging portion conforming to the forward soil engaging portionfor positioning thereon, the attaching end including a second impactreceiving surface for impacting the sweep to drive the sweep into thewedged position.
 25. The tool as set forth in claim 24 including asoil-engaging end opposite the removal end and adapted for clearing dirtand debris from the sweep assembly and an end support for supporting theremoval end from the sweep assembly with the engaging member in contactwith the retainer.
 26. The tool as set forth in claim 24 including asupport comprising a pair of sweep contact ears connected to the removalend for positioning the removal end relative to the sweep andmaintaining contact of the removal end with the sweep as the sweep isimpacted.
 27. A knock-on sweep assembly for mounting a tillage implementsweep with a forward soil entry portion on shank structure, the assemblyincluding a sweep support connected to the shank structure, a sweepmounting portion located rearwardly of the cutting edge and mating withthe sweep support, the sweep mounting portion providing a fastenerlesstight but releasable fit when the sweep is in a mounted position on thesweep support, and retaining structure for preventing the sweep fromdislodging from the sweep support, the retaining structure including acontact area on the mounting portion, and a retainer supported by thesweep support and having an end, the end offset from the sweep supportand biased into a locking position wherein the end abuts the contactarea when the sweep is in the mounted position and prevents the sweepfrom moving away from the mounted position until the end is moved towardthe sweep support against the bias, and wherein the sweep mountingportion includes a raised soil-deflecting portion located forwardly ofthe contact area on the mounting portion for directing soil and debrisaway from the contact area, the raised soil-deflecting portion defininga retainer receiving cavity providing support for the retainer when theend is in the locking position to thereby help the retainer resistbending forces.
 28. The sweep assembly as set forth in claim 27 whereinthe retainer comprises a bent wire.
 29. The sweep assembly as set forthin claim 28 including an aperture having an edge defining the contactarea on the mounting portion and wherein the bent wire includes an endportion having an axis extending perpendicularly to the contact area andan end face parallel to the contact area, and wherein a section of thewire adjacent the end portion is received within the cavity.
 30. Thesweep assembly as set forth in claim 27 including a soil deflectingsurface located between the cutting edge and the raised soil-deflectingportion for directing soil and debris away from the mounting portion andthe contact area.